In two-cycle internal combustion engines, it has been standard practice to introduce air and fuel into the crankcase of the engine and transfer it to the firing chamber of the cylinder through transfer ports along the side of the cylinder. This transfer takes place as the exhaust gases are exiting the cylinder. Thus, the fuel and air are being forced from the crankcase by the pressure created by the descending piston. Air is throttled into the crankcase which can result in a power loss and a decrease in efficiency.
It is an object of the present invention to provide a two-cycle engine design which embodies a revised cycle of air and fuel intake with a throttle control of exhaust gas as a means to control the power output of the engine.
Reference is made to a publication of the Society of Automotive Engineers, Inc., No. 790,501, presented at Congress and Exposition, Cobo Hall, Detroit, Michigan, U.S.A. Feb. 26-Mar. 2, 1979, entitled "Active Thermo-Atmosphere Combustion-A New Combustion Process for Internal Combustion Engines" by Shigeru Onishi et al.
Reference is also made to Japanese Pat. Preliminary Publications Nos. as follows 54-289816 - Mar. 3, 1979 (application 52-94133, Filed Aug. 8, 1977, Inventor - Shigeru Onishi) and 47-23708 - Oct. 13, 1972 (application 46-13382, Filed Mar. 11, 1971), Inventor - Shigeru Onishi).
The above-referenced material indicates the advantages and explains the combustion process of stratified charges of exhaust gases and fuel and air mixtures including the throttling of exhaust gases.
An object of the present invention is the provision of an air and fuel supply which effects a stratification of exhaust gas, air and fuel-air mixture to enhance the efficiency of the firing and combustion and also a complete engine design which utilizes the stratification and exhaust or scavenge control to provide a highly efficient operation.
A still further object of the engine design is the use of the incoming combustion air to cool the walls of the operating cylinder while imparting to the mixture a swirling action to position the fuel adjacent a spark plug to enhance the firing. In addition, an entrance valve and swirl pattern plate is provided at the cylinder head to further impart a circular motion which stratifies the air and the air and fuel mixture.
Additional features of the invention will be apparent in the following description and claims in which the principles of the invention are set forth together with details to enable persons skilled in the art to practice the invention all in connection with the best mode presently contemplated for the invention.